
Anna N. ChardCenters for Disease Control and Prevention | CDC
Anna N. Chard
Doctor of Philosophy
About
58
Publications
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Publications
Publications (58)
Background
To better establish the value of vaccination against influenza viruses, we estimated vaccine-averted influenza illnesses among young children and older adults in Chile, Guyana, and Paraguay.
Methods
We gathered country- and target population-specific data on monthly influenza hospitalizations, vaccine coverage, and vaccine effectiveness...
A global outbreak of clade II mpox associated with sexual contact, disproportionately affecting gay, bisexual, and other men who have sex with men (MSM), has been ongoing since May 2022. Information on types of contact most associated with transmission is limited. This report used data from a multijurisdictional vaccine effectiveness case-control s...
Background
Historically, lack of data on cost-effectiveness of influenza vaccination has been identified as a barrier to vaccine use in low- and middle-income countries. We conducted a systematic review of economic evaluations describing (1) costs of influenza illness; (2) costs of influenza vaccination programs; and (3) vaccination cost-effectiven...
Despite offering free-of-charge COVID-19 vaccines starting July 2021, Guatemala has one of the lowest vaccination rates in Latin America. From September 28, 2021 to April 11, 2022, we conducted a cross-sectional survey of community members, adapting a CDC questionnaire to evaluate COVID-19 vaccine access and hesitancy. Of 233 participants ≥12 years...
As of March 31, 2023, more than 30,000 monkeypox (mpox) cases had been reported in the United States in an outbreak that has disproportionately affected gay, bisexual, and other men who have sex with men (MSM) and transgender persons (1). JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic) was approved by the Food and Drug Administr...
Background:
In the United States, more than 30,000 cases of mpox (formerly known as monkeypox) had occurred as of March 1, 2023, in an outbreak disproportionately affecting transgender persons and gay, bisexual, and other men who have sex with men. In 2019, the JYNNEOS vaccine was approved for subcutaneous administration (0.5 ml per dose) to preve...
Objective:
To estimate the 2022 end-of-season influenza vaccine effectiveness (VE) against severe acute respiratory illness (SARI) hospitalization in Chile, Paraguay, and Uruguay.
Methods:
We pooled surveillance data from SARI cases in 18 sentinel surveillance hospitals in Chile (n=9), Paraguay (n=2), and Uruguay (n=7) during March 16-November 3...
Introduction
Historically, lack of data on cost-effectiveness of influenza vaccination has been identified as a barrier to vaccine use in low- and middle-income countries. We conducted a systematic review of economic evaluations describing (1) costs of influenza illness, (2) costs of influenza vaccination programs, and (3) vaccination cost-effectiv...
Despite offering free-of-charge COVID-19 vaccines starting July 2021, Guatemala has one of the lowest vaccination rates in Latin America. During September 28, 2021 to April 11, 2022, we conducted a cross-sectional survey of community members adapting a CDC questionnaire to evaluate COVID-19 vaccine access and hesitancy. Of 233 participants ≥12 year...
Background:
Diarrhoeal disease is a leading cause of childhood illness and death globally, and Shigella is a major aetiological contributor for which a vaccine might soon be available. The primary objective of this study was to model the spatiotemporal variation in paediatric Shigella infection and map its predicted prevalence across low-income an...
Background
In the Guatemala AGricultural workers and Respiratory Impact (AGRI) study, we evaluated the clinical and socioeconomic burdens of respiratory disease in a cohort of Guatemalan banana farm workers.
Methods
All eligible workers were offered enrollment from June 15–December 30, 2020, and annually, then followed for influenza-like illnesses...
We evaluated clinical and socioeconomic burdens of respiratory disease in banana farm workers in Guatemala. We offered all eligible workers enrollment during June 15-December 30, 2020, and annually, then tracked them for influenza-like illnesses (ILI) through self-reporting to study nurses, sentinel surveillance at health posts, and absenteeism. Wo...
The COVID-19 pandemic has affected influenza virus transmission, with historically low activity, atypical timing, or altered duration of influenza seasons during 2020-22 (1,2). Community mitigation measures implemented since 2020, including physical distancing and face mask use, have, in part, been credited for low influenza detections globally dur...
Background
Diarrheal disease remains a leading cause of childhood illness and mortality and Shigella is a major etiological contributor for which a vaccine may soon be available. This study aimed to model the spatiotemporal variation in pediatric Shigella infection and map its predicted prevalence across low- and middle-income countries (LMICs).
M...
Essential agricultural workers work under occupational conditions that may increase the risk of SARS-CoV-2 exposure and transmission. Data from an agricultural worker cohort in Guatemala, and anti-SARS-CoV-2 nucleocapsid IgG (anti-N IgG) testing were used to estimate past infections and analyze risk factors associated with seropositivity at enrollm...
We evaluated the clinical and socioeconomic burdens of respiratory disease in a cohort of Guatemalan banana plantation workers. All eligible workers were offered enrollment from June 15–December 30, 2020, and annually, then followed for influenza-like illnesses (ILI) through: 1) self-reporting to study nurses, 2) sentinel surveillance at health pos...
Background:
Afghanistan is one of two countries with endemic wild poliovirus type 1 (WPV1). The oral poliovirus vaccine (OPV) is the predominant vaccine used for polio eradication. Although OPV has been administered in routine childhood immunization and during frequent supplementary immunization activities, WPV1 continues to circulate in Afghanist...
COVID-19 has disproportionately affected persons who identify as non-Hispanic American Indian or Alaska Native (AI/AN) (1). The Blackfeet Tribal Reservation, the northern Montana home of the sovereign Blackfeet Nation, with an estimated population of 10,629 (2), detected the first COVID-19 case in the community on June 16, 2020. Following CDC guida...
In the United States, approximately 180,000 patients receive mental health services each day at approximately 4,000 inpatient and residential psychiatric facilities (1). SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), can spread rapidly within congregate residential settings (2-4), including psychiatric facilities. On April 1...
Since the Global Polio Eradication Initiative (GPEI) was established in 1988, two of the three wild poliovirus (WPV) serotypes (types 2 and 3) have been eradicated.* Transmission of WPV type 1 (WPV1) remains uninterrupted only in Afghanistan and Pakistan. This report summarizes progress toward global polio eradication during January 1, 2018-March 3...
Though the health risks associated with poor access to water, sanitation, and hygiene (WASH) are well established, recent large-scale WASH trials have found limited impact on enteric disease. The aims of this study were to: 1. estimate the prevalence of enteropathogens among children <5, school-aged children, and adults; 2. model associations betwe...
Background:
Water, sanitation, and hygiene (WASH) in schools is promoted by development agencies as a modality to improve school attendance by reducing illness. Despite biological plausibility, the few rigorous studies that have assessed the effect of WASH in schools (WinS) interventions on pupil health and school attendance have reported mixed im...
Background:
Humans are susceptible to over 1400 pathogens. Co-infection by multiple pathogens is common, and can result in a range of neutral, facilitative, or antagonistic interactions within the host. Soil-transmitted helminths (STH) are powerful immunomodulators, but evidence of the effect of STH infection on the direction and magnitude of conc...
Adequate provision of safe water, basic sanitation, and hygiene (WASH) facilities and behavior change can reduce pupil absence and infectious disease. Increased drinking water quantity may also improve educational outcomes through the effect of hydration on attention, concentration, and short-term memory. A pilot study was conducted to adapt field...
Background
Evidence from recent studies assessing the impact of school water, sanitation and hygiene (WASH) interventions on child health has been mixed. Self-reports of disease are subject to bias, and few WASH impact evaluations employ objective health measures to assess reductions in disease and exposure to pathogens. We utilized antibody respon...
Prevalence of enteric and neglected tropical diseases among primary school children in Mali (n = 800).
(DOCX)
Map of study school locations.
Light gray regions were included in study sample; dark gray regions were not included. Dark gray circles indicate location of beneficiary schools; white circles indicate location of comparison schools.
(TIF)
Mean pupil antibody response by grade level.
Red line indicates cut-off value for infection (if it exists).
(TIF)
Purified antigen, antigen format, amount used in coupling, GST linked, and coupling buffer.
(DOCX)
Blood samples from 805 students attending 42 elementary schools in Mopti, Sikasso, and Koulikoro regions, and Bamako district in Mali participated in a school water, sanitation, and hygiene intervention. Immunoglobulin (Ig) G responses to several antigens/pathogens were assessed by a multiplex bead assay (MBA), and the recombinantTaenia soliumT24H...
Evidence of the impact of water, sanitation, and hygiene (WASH) in schools (WinS) interventions on pupil absence and health is mixed. Few WinS evaluations rigorously report on output and outcome measures that allow for comparisons of effectiveness between interventions to be made, or for an understanding of why programs succeed. The Water, Sanitati...
Background:
Rates of drug and alcohol use are higher among men who have sex with men (MSM) than the general adult male population, and are often associated with increased sexual risk-taking.
Objectives:
We aim to examine the prevalence of drunk or high sex and their associations with socio-demographic characteristics, gay social network size, an...
Background
Rates of new HIV infections continue to increase worldwide among men who have sex with men (MSM). Despite effective prevention strategies such as condoms and pre-exposure prophylaxis (PrEP), low usage of both methods in many parts of the world hinder prevention efforts. An individual’s perceptions of the risk of acquiring HIV and the ser...
The provision of safely managed sanitation in informal settlements is a challenge, especially in schools that require durable, clean, sex-segregated facilities for a large number of children. In informal settlements in Nairobi, school sanitation facilities demand considerable capital costs, yet are prone to breakage and often unhygienic. The privat...
Malaria serology through assaying for IgG against Plasmodium spp. antigens provides evidence into the infection history for an individual. The multiplex bead assay (MBA) allows for detection of IgG against multiple Plasmodium spp., and can be especially useful in many regions where Plasmodium falciparum is of primary clinical focus, but other speci...
Dried blood spots (DBS) were collected from 805 children attending 42 elementary schools in the regions of Mopti, Sikasso, Koulikoro, and the regional capital of Bamako in Mali as part of an evaluation of a school health intervention. Eluted immunoglobulin (Ig) G from the DBS was assessed by a multiplex bead assay (MBA) for two filariasis antigens,...
There is a well-established link between hydration and improved cognitive performance among adults, with evidence of similar findings among children. No trials have investigated the impact of water provision on cognitive performance among schoolchildren in hot and arid low-resource settings. We conducted a randomized-controlled trial in five school...
Codebook from Mali pilot.
(XLSX)
Soil-transmitted helminths, a class of parasitic intestinal worms, are pervasive in many low-income settings. Infection among children can lead to poor nutritional outcomes, anaemia, and reduced cognition. Mass treatment, typically administered through schools, with yearly or biannual drugs is inexpensive and can reduce worm burden, but reinfection...
Experiences of homophobic discrimination are associated with an increased prevalence of psychological disorders and increased odds of reporting suicidal ideation among gay and bisexual men. We examine two domains of homophobia - external homophobic discrimination and internalised homophobia - and their associations with sexual orientation, demograp...
Adverse early life experiences (AELEs) are social interactions experienced by infants, children, and adolescents that may be inconsistent, threatening, neglectful, frightening, traumatic, or harmful and are risk factors for poor health outcomes. They involve interactions with individuals, the social or physical environment, the community, or societ...
The willingness of male-male dyads to use couples voluntary HIV counseling and testing (CVCT) has not been previously investigated globally among men who have sex with men (MSM). Using online advertisements, data were collected from 3245 MSM in seven countries who were ≥18 years of age and had ≥1 male sex partner in the previous 12 months. The anal...
Recent research suggests that men who have sex with men (MSM) experience intimate partner violence (IPV) at significantly higher rates than heterosexual men. Few studies, however, have investigated implications of heterosexist social pressures - namely, homophobic discrimination, internalized homophobia, and heterosexism - on risk for IPV among MSM...
Endorsed by the World Health Assembly in 2020, the Immunization Agenda 2030 strives to reduce morbidity and mortality from vaccine-preventable diseases across the life course (1). This report, which updates previous reports (2), presents global, regional,* and national vaccination coverage estimates and trends as of 2019 and describes the number of...